Journal of Krishna Institute of Medical Sciences University (Jan 2023)
Zingerone improves memory impairment in Wistar rats exposed to cadmium via modulation of redox imbalance
Abstract
Background: Our environment exposes us to various neurotoxins that can invariably affect cognitive ability. Aim and Objectives: To evaluate the modulatory role of zingerone on cadmium induced memory impairment, oxidative stress and apoptosis on the hippocampus of male Wistar rats. Material and Methods: Thirty (30) adult male Wistar rats used were grouped into six (6) groups, (n = 5) as follows; Control group (A), Group B was given 5 mg/kg of cadmium for twenty one days, Group C received 200 mg/kg b.w.t. of zingerone (C) for 21 days, the treatment study Groups D-F were given 5 mg/kg of cadmium for seven days and treated using varying dose of zingerone for 14 days (50 mg/kg, 100 mg/kg and 200 mg/kg b.w.t.). Zingerone and cadmium chloride were dissolved in normal saline, the route of administration was oral and the administration period was twenty-one days. Y–maze neurobehavioral test was used to evaluate spatial activity and spatial memory using number of arm entries, time spent in novel arm, number of correct spontaneous alternation and percentage alternation. On day 22, the animals were sacrificed, brain was removed and samples collected for biochemical analysis, histological and immunohistochemical investigations. Results: Administration of zingerone resulted in significant increased (p< 0.05) time in novel arm, number of arm entries, spontaneous alternations and percentage alternations when compared to rats that received cadmium only. This is indicating that zingerone improve the memory ability of Wistar rats exposed to cadmium. Cadmium intoxication increased the levels of Superoxide Dismutase (SOD), Catalase (CAT), Glutathione Peroxide (GPx) and decreased level of Malondialdehyde (MDA) as shown in Group B, however this was attenuated in Groups C-F that were treated with zingerone. Result also showed neuronal cell death, degenerative changes fragmented pyramidal and granular layer, loss of cytoplasmic content and pyknotic nuclei, evident in the histology and immunohistochemical study of the hippocampus of rats in Group B; however, these effects were reversed by zingerone in all Groups D-F. Conclusion: These findings suggest that zingerone may protect against cadmium mediated memory impairment, apoptosis and oxidative stress in the hippocampus.
